Side gate nozzle assembly

ABSTRACT

Disclosed is a side gate nozzle assembly ( 108 ) having a nozzle body ( 210 ) and at least one side gate nozzle tip assembly ( 112 ) wherein the nozzle body ( 210 ) and the at least one side gate nozzle tip assembly ( 112 ) are slidably engaged to each other.

TECHNICAL FIELD

Aspects relate generally to a side gate nozzle assembly and morespecifically to a side gate nozzle assembly having at least one sidegate nozzle tip assembly slidably engaged with respect to a nozzle body.

BACKGROUND

Side gate nozzle assemblies are generally known in the prior art. Inthese prior art assemblies, the side gate nozzle tip assemblies aremostly fixed to the nozzle body of the side gate nozzle assemblies.During thermal heat up, the nozzle body expands in at least thelongitudinal direction thereby relocating the side gate nozzle tipassemblies along the longitudinal axis. In addition, a manifold alsoexpands forcing the nozzle body along the longitudinal direction. Onedisadvantage with the prior art systems is gate alignment during andafter thermal heat up. A slight offset between the side gate nozzle tipassemblies and orifices of the cavity negatively impacts quality andpotentially increases downtime.

SUMMARY

In one aspect, there is a side gate nozzle assembly having a nozzle bodyand at least one side gate nozzle tip assembly, wherein the nozzle bodyand the at least one side gate nozzle tip assembly are slidably engagedwith respect to each other.

In another aspect, there is a side gate nozzle assembly having a nozzlebody, and at least one side gate nozzle tip assembly retained to acavity member but not fixed to the nozzle body.

In still another aspect, there is a side gate nozzle assembly having anozzle body with a melt channel and at least one side gate nozzle tipassembly with a melt channel in fluid communication with the meltchannel of the nozzle body, wherein the at least one side gate nozzletip assembly is retained to a cavity member.

In still yet another aspect, there is a side gate nozzle assembly havinga nozzle body and at least one side gate nozzle tip assembly, whereinthe at least one side gate nozzle tip assembly has at least onecompliant member for operably sealing the at least one side gate nozzletip assembly to the nozzle body.

Other aspects and features will now become apparent to those skilled inthe art upon review of the following detailed description with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The non-limiting embodiments will be more fully appreciated by referenceto the following detailed description of the non-limiting embodimentswhen taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a cross sectional view of a hot runner system (100) having aside gate nozzle assembly (108) engaged to a mold plate (240).

FIG. 2 is a cross sectional view of the hot runner system (100) havingthe side gate nozzle assembly (108) not fully engaged to the mold plate(240).

FIG. 3 is an isometric exploded view of a side gate nozzle tip assembly(112) along with a cavity member (110).

FIGS. 4A, 4B are an isometric exploded view and cross sectional view ofan alternative embodiment of the side gate nozzle tip assembly (112)shown in FIG. 3.

FIGS. 5A, 5B are an isometric exploded view and cross sectional view ofan alternative embodiment of the side gate nozzle tip assembly (112)shown in FIGS. 3 and 4.

FIGS. 6A, 6B are an isometric exploded view of an alternative embodimentof the side gate nozzle tip assembly (112) shown in FIGS. 3-5.

FIGS. 7A, 7B are an isometric exploded view of an alternative embodimentof the side gate nozzle tip assembly (112) shown in FIGS. 3-6.

FIG. 8 is an isometric exploded view of a plurality of the side gatenozzle tip assemblies (112) in a mold insert receiver (241) of the moldplate (240).

FIG. 9A, 9B, 9C are cross sectional views of the hot runner system (100)including the side gate nozzle assembly (108) in a cold state.

FIG. 10A, 10B, 10C are cross sectional views of the hot runner system(100) including the side gate nozzle assembly (108) in a hot state.

The drawings are not necessarily to scale and may be illustrated byphantom lines, diagrammatic representations and fragmentary views. Incertain instances, details not necessary for an understanding of theembodiments (and/or details that render other details difficult toperceive) may have been omitted.

DETAILED DESCRIPTION

FIG. 1 illustrates a side gate nozzle assembly (108) in a hot runnersystem (100). The hot runner system (100) is engaged to a mold plate(240), which is referred to hereinafter as being in the engagementstate. In the engagement state, a melt channel (216) of a nozzle body(210) and a melt channel (298) of a side gate nozzle tip assembly (112)are in fluid communication with each other.

The side gate nozzle assembly (108) may include but is not limited tothe nozzle body (210) and the side gate nozzle tip assembly (112). Theside gate nozzle assembly (108) may also include but Is not limited to:(i) a nozzle heater (212) that is connected with the nozzle body (210),(ii) a nozzle tip heater (214) that is connected to a tip region of thenozzle body (210), (iii) the melt channel (216) of the nozzle body(210), and (iv) a nozzle aligner (218), which is ring shaped forconvenience, and the nozzle aligner (218) defining a slot (219) forreceiving a dowel (not shown) so that the nozzle body (210) may beoriented relative to the cavity member (110), and (v) a locatinginsulator (220), which is received in a pocket defined by the manifoldplate (204). The locating insulator (220) receives the nozzle body (210)and maintains position of the nozzle body (210) relative to the manifoldplate (204), and also acts to thermally insulate the nozzle body (210)from the manifold plate (204). The side gate nozzle assembly (108) mayalso include but is not limited to a spring member (222) that is placedbetween the locating insulator (220) and the nozzle aligner (218), orbetween the locating insulator (220) and the outer extending flangedportion of the nozzle body (210). The manifold (106) defines a meltchannel (109) that is in fluid communication with the melt channel (216)of the nozzle body (210).

The side gate nozzle tip assembly (112) of the hot runner system (100)engages a cavity member (110). The nozzle body (210) is slidably engagedwith the side gate nozzle tip assembly (112). When the side gate nozzletip assembly (112) becomes disengaged from the nozzle body (210), theside gate nozzle tip assembly (112) remains retained to the cavitymember (110), and the nozzle body (210) remains retained to a portion ofthe hot runner system (100), as is shown in FIG. 2.

Referring again to FIG. 1, the hot runner system (100) also includes butis not limited to: (i) a backing plate (202), (ii) a manifold plate(204), (iii) a manifold (106), which is received and supported betweenthe manifold plate (204) and the backing plate (202), and (iv) amanifold locating insulator (288), which is located between the manifoldplate (204) and the manifold (106). The manifold locating insulator(288) is used to thermally insulate, at least in part, the manifold(106) from the manifold plate (204). A back up insulator (206) islocated between the manifold (106) and backing plate (202). A connector(207) is used to connect the back up insulator (206) with the manifold(106). The back up insulator (206) is used to thermally insulate themanifold (106) from the backing plate (202), and to position the nozzlebody (210) longitudinally. The hot runner system (100) may furtherinclude but is not limited to: (i) a sprue (230) that defines a spruemelt passageway (232), (ii) a sprue heater (234) that is connected withthe sprue (230), and (iii) a locating ring (236) mounted to the backingplate (202), and the locating ring (236).

Turning now to FIG. 2 which illustrates the hot runner system (100)disengaged from the mold plate (240), which is referred to as being inthe disengagement state. In the disengagement state, the melt channel(216) of the nozzle body (210) and the melt channel (298) of the sidegate nozzle tip assembly (112) are not in fluid communication with eachother because of the separation of the nozzle body (210) from the sidegate nozzle tip assembly (112).

The hot runner system (100) and the mold plate (240) are movablerelative to each other between the engagement state (FIG. 1) and thedisengagement state (FIG. 2). Specifically, the hot runner system (100)and the mold plate (240) are movable towards and away from each otheralong a direction (211) between the engagement state and thedisengagement state. In the engagement state as that shown in FIG. 1,the hot runner system (100) engages the mold plate (240) so that theside gate nozzle tip assembly (112) becomes engaged with the nozzle body(210) so that in operation the side gate nozzle tip assembly (112) isslidably engaged to the nozzle body (210). In the disengagement state asthat shown in FIG. 2, the hot runner system (100) disengages orseparates from the mold plate (240) so that the side gate nozzle tipassembly (112) becomes disengaged and separated from the nozzle body(210) while: (i) the side gate nozzle tip assembly (112) remainsretained to the cavity member (110), and (ii) the nozzle body (210)remains retained to a portion of the hot runner system (100).

Referring again to FIG. 2, a manifold-nozzle interface (116) is depictedwhere a head (296) of the nozzle body (210) interfaces with the manifold(106). A nozzle-tip interface (114) is depicted where a distal end (294)of the nozzle body (210) interfaces with the side gate nozzle tipassembly (112) in the engagement state as that shown in FIG. 1. FIG. 1shows the nozzle-tip interface (114) wherein the melt channel (216) ofthe nozzle body (210) is in fluid communication with the melt channel(298) of the side gate nozzle tip assembly (112).

The cavity member (110) may be a cavity plate, cavity insert, gateinsert, mold insert, or other device inserted in a mold (hereincollectively referred to as “cavity member (110)”). In an alternativeembodiment, the cavity member (110) may be made up of one or morecomponents. The side gate nozzle tip assembly (112) is in fluidcommunication with the cavity member (110).

The nozzle body (210) is in fluid communication with the manifold (106)and the side gate nozzle tip assembly (112). The nozzle body (210) andthe side gate nozzle tip assembly (112) are slidably engaged withrespect to each other while the side gate nozzle tip assembly (112)remains in fluid communication with the cavity member (110), and thenozzle body (210) remains in fluid communication with the manifold(106).

The nozzle body (210) and the side gate nozzle tip assembly (112) areseparable from each other without the side gate nozzle tip assembly(112) losing tip location relative to the cavity member (110) as shownin FIG. 2. The side gate nozzle tip assembly (112) remains retained tothe cavity member (110) while the nozzle body (210) remains retained toa portion of the hot runner system (100) in the disengagement state.

Referring now to FIG. 3, a compliant member (306), such as a Bellevillespring, is used to force the side gate nozzle tip assembly (112) intoslidable but sealing engagement with the nozzle body (210) duringoperation and while the sliding movement between the side gate nozzletip assembly (112) and the nozzle body (210) occur during thermalexpansion created by heat up to operational temperature. During heat up,there is thermal expansion of the nozzle body (210) in, among otherdirections, the longitudinal direction. During the heat up or thermalexpansion stage, the compliant member (306) maintains the side gatenozzle tip assembly (112) in sealing engagement with the nozzle body(210) such that there is sufficient sealing pressure to preclude leakagewhile simultaneously allowing the nozzle body (210) to be in sliding andsealing engagement with the side gate nozzle tip assembly (112). Thenozzle body (210) is not fixed or fixedly coupled to the side gatenozzle tip assembly (112).

In one embodiment, the side gate nozzle tip assembly (112) may include anozzle tip receiver (111) configured to accommodate the side gate nozzletip assembly (112). The side gate nozzle tip assembly (112) may alsoinclude but is not limited to: (i) a tip body (302), (ii) a seal (304),which may be ring shaped, (iii) the compliant member (306), (iv) aninsulator (388), and (v) a retention member (310), such a retainer,clip, various other retention devices, etc.

The insulator (388) is received in the nozzle tip receiver (111) and isprovided for creating a thermal barrier. The insulator (388) alsolocates and supports the side gate nozzle tip assembly (112). Thecompliant member (306) is then inserted against the insulator (388). Thecompliant member (306) biases the side gate nozzle tip assembly (112)against the nozzle body (210) at sufficient pressure to preclude leakageof the molten plastic from the melt channels (216, 298) while allowingsliding engagement between the nozzle body (210) and the side gatenozzle tip assembly (112). The seal (304) is attached to the tip body(302) for sealing and for locating the side gate nozzle tip assembly(112). The seal (304) may be press fit, snap fit, interference fit,welded, brazed, soldered, etc. to the tip body (302).

The tip body (302) along with the seal (304) is placed into the nozzletip receiver (111) so as to abut the compliant member (306). Theretention member (310) then abuts the seal (304) so as to retain the tipbody (302) to the cavity member (110) thus the side gate nozzle tipassembly (112) is retained to the cavity member (110). It will beappreciated that various tip geometries may be used. Various insulatorgeometries are also possible. Each side gate nozzle tip assembly (112)is individually retained to its own mold cavity via the retention member(310), and this arrangement eases assembly, maintenance andmanufacturing.

FIGS. 4A and 4B are an alternative embodiment of the side gate nozzletip assembly (112) shown in FIG. 3. In this embodiment, the tip body(302) is assembled in a bore (422) of a threaded retainer (398). Thecomplaint member (306) is slid over a first end (424) of the tip body(302) and then a sleeve (420) traps the compliant member (306) betweenthe tip body (302) and the sleeve (420). The sleeve (420) may be pressfit, snap fit, interference fit, welded, brazed, soldered, etc. to thefirst end (424) the tip body (302). The seal (304) may be press fit,snap fit, interference fit, welded, brazed, soldered, etc. to a secondend (426) the tip body (302). After the seal (304), the threadedretainer (398), the compliant member (306), the sleeve (420) areassembled to the tip body (302), the side gate nozzle tip assembly (112)is threaded to the nozzle tip receiver (111) of the cavity member (110).

The compliant member (306) biases the side gate nozzle tip assembly(112) against the nozzle body (210) at sufficient pressure to precludeleakage of the molten plastic from the melt channels (216, 298) whileallowing sliding engagement between the nozzle body (210) and the sidegate nozzle tip assembly (112).

FIGS. 5A and 5B are an alternative embodiment of the side gate nozzletip assembly (112) shown in FIGS. 3 and 4. In this embodiment, the tipbody (302) is slipped through bores in the compliant member (306),threaded retainer (398), and the seal (304). A retaining ring (390)placed on the tip body (302) retaining the compliant member (306) andthe threaded retainer (398) to the tip body (302). The seal (304) may bepress fit, snap fit, interference fit, welded, brazed, soldered, etc. toa second end (426) the tip body (302). After the seal (304), thethreaded retainer (398), the compliant member (306), and the retainingring (390) are assembled to the tip body (302), the side gate nozzle tipassembly (112) is threaded to the nozzle tip receiver (111) of thecavity member (110).

The compliant member (306) biases the side gate nozzle tip assembly(112) against the nozzle body (210) at sufficient pressure to precludeleakage of the molten plastic from the melt channels (216, 298) whileallowing sliding engagement between the nozzle body (210) and the sidegate nozzle tip assembly (112).

FIGS. 6A and 6B are an alternative embodiment of the side gate nozzletip assembly (112) shown in FIGS. 3-5. In this embodiment, the twocompliant members (306) are slid over the second end (426) of the tipbody (302) and then the retainer (308) is slid over the second end (426)of the tip body (302). The retainer (308) may be slip fit, press fit,snap fit, interference fit, etc. to the second end (426) of the tip body(302). Then the seal (304) may be press, fit, snap fit, interferencefit, welded, brazed, soldered, etc. to the second end (426) the tip body(302). The seal (304) has a shoulder that prohibits the removal of theretainer (308) and compliant members (306) from the nozzle tip assembly.After the retainer (308), the compliant members (306), the seal (304)are assembled to the tip body (302), the side gate nozzle tip assembly(112) is press fit into the nozzle tip receiver (111) of the cavitymember (110).

The compliant member (306) biases the side gate nozzle tip assembly(112) against the nozzle body (210) at sufficient pressure to precludeleakage of the molten plastic from the melt channels (216, 298) whileallowing sliding engagement between the nozzle body (210) and the sidegate nozzle tip assembly (112).

FIGS. 7A and 7B are an alternative embodiment of the side gate nozzletip assembly (112) shown in FIGS. 3-6. In this embodiment, the seal(304) may be press fit, snap fit, interference fit, welded, brazed,soldered, etc. to the second end (426) of the tip body (302). Thecompliant member (306) is slid over the second end (426) of the tip body(302). A tab (410) is assembled to the first end (424) of the tip body(302). After the seal (304), the compliant member (306), and the tab(410) are assembled to the tip body (302), a spring pin (412) is placedthrough a bore in the tab (410) and a hole in the cavity member (110).The spring pin (412) has an interference fit with the bore in the tab(410) and the hole in the cavity member (110), thereby retaining the tipbody (302) to the cavity member (110).

The compliant member (306) biases the side gate nozzle tip assembly(112) against the nozzle body (210) at sufficient pressure to precludeleakage of the molten plastic from the melt channels (216, 298) whileallowing sliding engagement between the nozzle body (210) and the sidegate nozzle tip assembly (112).

FIG. 8 is a plurality of the side gate nozzle tip assemblies (112) in amold insert receiver (241) of the mold plate (240) or multi-cavityembodiment of the hot runner system (100). A plurality of the side gatenozzle tip assemblies (112) are individually installed in the moldinsert receiver (241) of the mold plate (240). A cover plate (244) isretained to the mold plate (240) with screws (246). The cover plate(244) precludes the introduction of contaminants to tip areas (notshown). This arrangement allows for easy handling in assembly andservice in the press of individual gates.

FIGS. 9A, 9B, 9C are cross sectional views of the hot runner system(100) in FIG. 1 in the non-operational or cold condition.

In FIG. 9A, the manifold nozzle interface (116) is depicted where thenozzle body (210) interfaces with the manifold (106), and the nozzle tipinterlace (114) is depicted where the nozzle body (210) interfaces withthe side gate nozzle tip assembly (112).

In FIG. 9B, the manifold nozzle interface (116) is depicted. Before themanifold (106) and the nozzle body (210) are heated to full operationaltemperature or as shown in their non-heated state, the melt channel(109) of the manifold (106) is offset or not aligned with the meltchannel (216) of the nozzle body (210). During heat up as explained inFIGS. 10A, 10B, 10C, the offset is eliminated.

In FIG. 9C, the nozzle tip interface (114) is depicted. The tip body(302) has a melt channel (298), and the nozzle body (210) has a meltpassageway (804). The melt passageway (804) of the nozzle body (210) andthe melt channel (298) of the tip body (302) are offset in thenon-heated state. During heat up as explained in FIGS. 10A, 10B, 10C,the offset is eliminated.

FIGS. 10A, 10B, 10C are cross sectional views of the hot runner system(100) of FIG. 1 in the operating condition or its heated state.Specifically, the manifold (106) and the nozzle body (210) have beenheated to their operating temperature and the hot runner system (100) isat its operational temperature.

In FIG. 10A, the manifold-nozzle interface (116) is depicted where thenozzle body (210) interfaces with the manifold (106). The nozzle-tipinterface (114) is depicted where the nozzle body (210) interfaces withthe side gate nozzle tip assembly (112).

In FIG. 10B, the manifold-nozzle interface (116) is depicted. The hotrunner system (100) is shown at its operating temperature. In theoperating temperature, the melt channel (109) of the manifold (106) isaligned with the melt channel (216) of the nozzle body (210).

As the manifold (106) is heated to its operating temperature, themanifold (106) expands causing the melt channel (109) of the manifold(106) to shift for example to the right so that the melt channel (109)of the manifold (106) aligns with the melt channel (216) of the nozzlebody (210) when the manifold (106) is fully heated to its operatingtemperature as shown in FIG. 10B.

In FIG. 10C, the nozzle-tip interface (114) is depicted. The hot runnersystem (100) is shown at its operating temperature. At the operatingtemperature, the melt passageway (804) of the nozzle body (210) and themelt channel (298) of the tip body (302) are aligned in the heatedstate.

As the manifold (106) and the nozzle body (210) are heated to theiroperating temperatures, the manifold (106) and the nozzle body (210)expand causing the melt passageway (804) of the nozzle body (210) tomove for example downward in FIG. 10C such that the melt passageway(804) of the nozzle body (210) and the melt channel (298) of the tipbody (302) align with each other.

The nozzle body (210) defines external surfaces (213) perpendicular tothe side gate nozzle tip assembly (112) axis's and parallel to thenozzle body (210) axis's. The external surfaces (213) permit relativemovement between the nozzle body (210) and the side gate nozzle tipassemblies (112) when the manifold (106) and the nozzle body (210) areheated to operating temperature as that shown in FIG. 10C. The manifold(106) and nozzle body (210) will expand along the longitudinal direction(502), and as a result, the distal end 294 of the nozzle body (210) willbe pushed toward the cavity. To accommodate the longitudinal movement ofthe nozzle body (210) between the cold state and operational or hotstate of the hot runner system (100), the external surface (213) permitsrelative movement between the nozzle body (210) and the side gate nozzletip assembly (112). The side gate nozzle tip assembly (112) and thenozzle body (210) of the side gate nozzle assembly (108) selectivelyengage one another or abut one another, but they are not fastened toeach other.

In one embodiment, the external surfaces (213) are flat surfaces. Thefirst end (424) of the tip body (302) slidably engages the flat surface.

The alignment of the second end (426) of the nozzle body (302) or tip ofthe side gate nozzle tip assembly (112), to the mold gate or cavityorifice influences part quality, gate vestige, cycle time, pressure dropand balance. The position of the side gate nozzle tip assembly (112) inthe plane perpendicular to the lateral melt channel axis is governed bythe seal (304). The position of the side gate nozzle tip assembly (112)along the lateral melt channel axis is governed by the nozzle body(210). The sliding contact between the side gate nozzle tip assembly(112) and the external surface (213) of the nozzle body (210) allowsthermal expansion of the nozzle body (210) to be independent of the sidegate nozzle tip assembly (112) position. The position of the nozzle body(210) in the plane perpendicular to the longitudinal axis of the nozzlebody (210) is governed by the locating insulator (220) and the nozzlebore in the manifold plate (204). This position is constant (coldposition and hot position) and therefore the position of the axis of thenozzle body. (210) is constant.

General Discussion

Some of the embodiments and aspects provided provide a side gate nozzleassembly (108) that is, at least in part, more robust, user-friendly forassembly and serviceability, reduced leakage capacity, largertemperature window capability for use in the hot runner system (100).The embodiment and aspects described herein may allow for the side gatenozzle assembly (108) to be aligned to the mold gate without the needfor a telescoping nozzle head or a nozzle link (for example).

Other, possible advantages of the aspects and embodiments describedherein are the ease of assembly, maintenance, and serviceability. Theassembly sequence is much easier and faster than the other knownsystems. The assembly does not require extreme skill or multipleoperators as when using cavity pods or split cavities. For example, acommon occurrence among side gate molders is that they have to stopevery so often in order to clean a blocked gate. Since this is downtime, they would like to minimize this interruption. With the knownsystems using cavity pods, they are unable to remove just the cavitiesthat are having the issues. They have to remove the entire set ofcavities that are associated with the cavity pod in order to clean ablocked gate of a known hot-runner system. Then, they have to go throughthe complicated and cumbersome assembly procedure requiring a veryskilled assembler. Users of split cavities are able to remove half ofthe cavity that is having issues but the tip will remain in place withthe other cavity half still in the cavity plate. If the entire cavityneeds to be disassembled from the mold then all cavity halves associatedwith the nozzle head along with the nozzle head itself would need to beremoved. The embodiments and aspects described herein may allow, atleast in part, for a faster and easier serviceability for cleaning ablocked gate compared to the known systems, as the embodiments andaspects allow for the ability to only remove the mold cavities that arehaving issues while leaving the other mold cavities undisturbed.

An embodiment or aspect provides coupling the side gate nozzle tipassembly (112) to the cavity member (110) providing gate alignment, andhaving the side gate nozzle tip assembly (112) in fluid communicationwith the nozzle body (210) but not attached or fixed to the nozzle body(210). The Interface between the side gate nozzle tip assembly (112) andthe nozzle body (210) may be allowed to slide. The relative slidingmotion (between the side gate nozzle tip assembly (112) and the nozzlebody (210) accommodates the thermal growth of the hot runner system(100). In a cold state, the side gate nozzle tip assembly (112) may beretained to the cavity member (110), aligned with the cavity member(110), and in fluid communication with the nozzle body (210). The meltpassageway (804) of the nozzle body (210) may not be in alignment withthe melt channel (298) in the side gate nozzle tip assembly (112) (inthe cold state or condition). As the hot runner system (100) is heatedup, the side gate nozzle tip assembly (112) remain coupled or retainedto the cavity member (110), aligned with the cavity member (110), and influid communication with the nozzle body (210). The nozzle body (210)will expand in length and slide against the face of the side gate nozzletip assembly (112) (as the hot runner system (100) continues to beheated). As the nozzle body (210) thermally expands, the melt passageway(804) in the nozzle body (210) will become closer to alignment with themelt channel (298) in the side gate nozzle tip assembly (112). In thehot condition (that is, at operating temperature), the side gate nozzletip assembly (112) remains coupled to the cavity member (110), alignedwith the cavity member (110), and in fluid communication with the nozzlebody (210). The melt passageway (804) within the nozzle body (210) is inalignment with the melt channel (298) of the side gate nozzle tipassembly (112), as illustrated in FIGS. 10A, 10B, 10C. The spring member(222), such as Bellville washer, or other load generating compliantfeature, may be used to ensure that the side gate nozzle tip assembly(112) remains in fluid communication with the nozzle body (210) andprovide the required sealing force at this interface.

The side gate nozzle tip assembly (112) would first be coupled to themold cavities. The mold cavities would then be assembled within a cavityplate with a cover plate for safety and protection, etc. The cover plate(244) precludes the introduction of contaminants to the tip area. Thehot runner system (100) would be assembled and include among others thesprue (230), the manifold (106), and the nozzle body (210), the springmember (222), the locating insulator (220), and the back up insulator(206) placed in a manifold plate and covered with a backing plate. Thecavity plate and the hot runner system (100) would then be assembledtogether, as depicted in the FIGS.

The sequence for cleaning a blocked mold gate or for any serviceabilityis as follows: first, the cavity plate should be unfastened from the hotrunner assembly and should be latched to the core side of the mold. Theplatens of the molding system are then opened in order to break theplastic slugs between the side gate nozzle tips and the nozzle bodies.The cavity plate may then be unlatched from the core side of the moldand reattached to the hot runner system (100). The platens are thenopened along that the parting line of the mold. From here, the coverplates over the drops having any negative issues may be removed. Oncethe cover plates are removed, then there is complete access to the moldcavities themselves. Individual mold cavities are now able to be removedfrom the cavity plate. Only the mold cavities with issues need to bepulled from the system. Once the mold cavity is removed, the side gatenozzle tip retained to the mold cavity may be disassembled allowingaccess to the mold gate for cleaning, etc. After the blockage has beenremoved, the side gate nozzle tip may be reassembled to the mold cavity,and the mold cavity placed backed into the cavity plate and protectedwith the cover plate.

It is noted that the foregoing has outlined some of the more pertinentnon-limiting aspects or embodiments. Thus, although the description ismade for particular arrangements and methods, the intent and concept ofthe aspects and embodiments is suitable and applicable to otherarrangements and applications. It will be clear to those skilled in theart that modifications to the disclosed aspects or embodiments can beeffected without departing from the scope the independent claims. It isunderstood that the described aspects or embodiments are merelyillustrative of the independent claims.

What is claimed is:
 1. A side-gated injection molding apparatuscomprising: an injection manifold assembly for distributing a meltstream of moldable material to a plurality of mold cavities of a moldthat are aligned on opposing sides of the injection manifold assembly,the injection manifold assembly having a plurality of melt passagewayswith each melt passageway being in fluid communication with a respectivemold cavity of the plurality of mold cavities, and a plurality of sidegate nozzle tip assemblies for receiving the melt stream from theplurality of melt outlets of the injection manifold assembly anddelivering the melt stream to the plurality of mold cavities, whereineach nozzle tip assembly includes a nozzle tip coaxially received withina gate seal structure and wherein the gate seal structure includes aninner sealing component coupled within an outer sealing component suchthat relative positioning between said components applies a sealingpreload between the nozzle tip assembly and a first surface proximate toa respective melt outlet of said nozzle tip assembly and a secondsurface surrounding a respective mold gate of a corresponding moldcavity.
 2. The side-gated injection molding apparatus of claim 1,wherein the injection manifold assembly further includes an injectionmanifold portion having opposing side surfaces in which the plurality ofmelt passageways are formed.
 3. The side-gated injection moldingapparatus of claim 2, wherein the first surface proximate to arespective melt passageway is a respective side surface of the injectionmanifold portion that surrounds the melt passageway against which anupstream surface of at least one of the nozzle tip and the inner sealcomponent of the associated nozzle tip assembly are slidably disposed soas to accommodate thermal expansion.
 4. The side-gated injection moldingapparatus of claim 3, wherein the injection manifold is T-shaped.
 5. Theside-gated injection molding apparatus of claim 1, wherein the outersealing component includes a face seal surface for contacting andsealing against the second surface surrounding the respective mold gateof the corresponding mold cavity.
 6. The side-gated injection moldingapparatus of claim 2, wherein a downstream end of the inner sealingcomponent includes an outer circumferential surface for contacting andsealing against a bore that is coaxial with and leads to the respectivemold gate of the corresponding mold cavity.
 7. The side-gated injectionmolding apparatus of claim 1, wherein a downstream end of each nozzletip assembly is received within a bore that surrounds a mold gate of therespective mold cavity associated therewith.